1. Field
The present disclosure relates generally to power door lock systems for vehicles.
2. Description of the Problem and Related Art
Today “multi-tasking” is the normal mode of operation. The act of shopping or going to a doctor appointment could involve collecting items to return to the store, making sure that all the required documentation is in hand, installing a sun shade behind the windshield, hiding valuables left in the car, transferring a child to a stroller, completing a cell phone call, making sure the child has juice and toys, and then, when you are walking in the mall or are being seen by the doctor, the thought hits you—“Did I lock the car?”
Reminder devices have been developed, but these are “dumb” devices which are not fool-proof. For example, U.S. Pat. No. 8,242,922, to Varasteh, teaches a reminder device including a controller, a switch, and an annunciator. The device may be adhered over the “lock” button on a remote car lock fob. When a user presses the “lock” button and closes the switch, the controller turns on the annunciator for a fixed period of time, for example, two hours to ten hours. The annunciator may be a light source such as a flashing LED or an audio indicator. The signal from the annunciator is intended to communicate to a user that the car door has been locked. However, if the user pushes the “lock” button while out of range of the car, or pushes the “unlock” button after locking a car door, the annunciator will erroneously indicate that the car door has been locked. Further, the “dumb” annunciator remains activated for a fixed period of time. This fixed period of activation results in two problems. First, the annunciator is draining the battery during the entire pre-programmed period of annunciation. Second, if the user desires to verify the locked condition of the vehicle after the pre-programmed period, e.g., after a party or after sleeping overnight, the device cannot provide an answer. Further, the annunciator will indicate that the doors are locked even in the event that there is an electrical malfunction of the door locking system, or if a door is mechanically not fully closed preventing engagement of one or more of the locks.
A user may enter a house and only then decide to lock the vehicle. Pushing the remote vehicle lock button would trigger any of the available “dumb” reminders, but there would be no guarantee that the remote signal actually reached the vehicle and resulted in locking of the door.
U.S. Pat. No. 6,703,919, to Baset, teaches a system for confirming the lock status for a vehicle that consists of a prior art vehicle anti-theft system that is configured to energize the vehicles exterior lights or horn in response to a command from a remote keyless entry device. The remote device includes a lock button, a unlock button and a trunk open button. The remote device is further configured with a LED which shows status of the lock button and with control logic upon the execution of which the LED is energized to show whether the lock or unlock button were depressed. However, this status indicator can only indicate the status of the remote device buttons. The LED does not show whether the vehicle's power door locks actually received the signal from the remote and energized the door locks.
U.S. Pat. No. 7,504,931, to Nguyen, is directed to a remote device that can indicate a variety of conditions about a vehicle. The remote device includes a transceiver and a display for indicating status and is in communication with a vehicle electronics system with a controller that is configured to, among other things, energize door lock actuators. To provide feedback regarding whether a command like locking the doors has been completed, the controller interrogates sensors the responses from which represent whether the command was completed. Since this arrangement requires such sensors, it increases the complexity and expense of a system for remotely confirming a locked status of a vehicle.